The National Survey of Oral Health in Seniors was conducted by NIDR in cooperation with Westat, Inc. during 1985-86 and provides the baseline for the oral health status of U.S. non-institutionalized persons aged 65 and older. The sampling frame was provided by the Area Agencies on Aging and the sample consisted of all older persons who attended selected multi- purpose senior centers within a designated 12 month interval. The sample of 5,649 seniors represented over 4 million older persons aged 65-103 who attend senior centers in the U.S. Clinical assessments were made for coronal caries, root caries and periodontal destruction. Demographic and health histories were collected for each older person participating in the clinical examination. The specific aims of this effort were to document the survey design for the senior sample and to produce a public use data file including clinical protocols and the statistical methodologies for calculating national or regional estimates, weights, and sampling errors. The documented file generated by this effort and the accompanying hard copy documentation entitled "Public use data file documentation and survey methodology--Part II Seniors" is pending release by the National Archives.